Answer:
a) 4 s
b) 36 m/s²
c) 54 m
Explanation:
s = 2t³ – 24t + 6
a) Find t when v = 72 m/s.
v = ds/dt
v = 6t² – 24
72 = 6t² – 24
6t² = 96
t = 4
b) Find a when v = 30 m/s.
a = dv/dt
a = 12t
When v = 30:
30 = 6t² – 24
6t² = 54
t = 3
a = 36
c) Find Δs between t = 1 and t = 4
Δs = (2(4)³ – 24(4) + 6) – (2(1)³ – 24(1) + 6)
Δs = 38 – (-16)
Δs = 54
Light, being both a wave and a particle, displays many properties similar to both of them. Light, like waves, travels at different speeds through mediums because they provide any variable amount of resistance. Even air resists light to a degree, and light speed through air is slower than light speed in a vacuum.
Answer:
When she stretches her arms out,<em> B) her angular speed ω increases due to her moment of inertia decreasing</em>
Explanation:
The angular momentum of a rotating object is defined as the product of its moment of inertia and angular speed.
<em>L = I ω</em>
<em>where</em>
- <em>L is the angular momentum</em>
- <em>I is the moment of inertia</em>
- <em>ω is the angular speed</em>
<em />
According to the principle of conservation of angular momentum, if there is no external torque, angular momentum of the skater must remain conserved. If the initial and final moment of inertia is <em>I_i and I_f </em>while corresponding angular velocities are <em>ω_i and ω_f , </em>then the principle of conservation of angular momentum can be expressed as the following equation:
<em>(I_f) (ω_f) = (I_i) (ω_i)</em>
<em>ω_f / ω_i = I_i / I_f</em>
<em />
From the expression above, we can see that if the moment of inertia decreases, angular velocity would increase to conserve angular momentum of the skater.
Therefore, When she stretches her arms out,<em> her angular speed ω increases due to her moment of inertia decreasing.</em>
Ahhh, there aren’t option to work with :v
Try writing them down here thnx
Answer:
F = 7.143 kN
Explanation:
given,
time taken to apply break = 1.05 s
car slows down from 15 m/s to 9 m/s
mass of the car = 1250 Kg
force is equal to the change in momentum with respect to time.
F = -7142.85 N
F = - 7.143 kN
Force is acting opposite direction of velocity of car i.e. the sign is negative.
